Children with Attention Deficit Hyperactivity Disorder (ADHD) are characterized by symptoms of inattention, impulsivity, and motor excess, and are likely to display behavior problems, poor peer relationships, and academic difficulties. Developing effective treatments for ADHD is crucial, given that social, educational, and emotional difficulties frequently persist. It has recently been suggested that the academic failure experienced by many ADHD children may be critical, and that the appropriate focus of treatment may be their academic rather than behavior problems. Behavior therapy, the most widely studied non-medical intervention for ADHD, results in short-term improvements in academic and behavioral functioning, though long-term prognostic improvements have not been demonstrated. A major task for future research is to develop procedures for enhancing maintenance and generalization of treatment gains and to determine the mechanisms under which such procedures operate. One potential mechanism underlying treatment maintenance and generalization may be the extent to which treatments promote the transfer of behavioral control from external to intrinsic sources of motivation. A variety of reinforcement and task/instructional factors, such as feedback strategies, have been shown to affect intrinsic motivation in normal children and adults; of particular concern are the consistent findings that external reinforcers may actually undermine intrinsic motivation. While this phenomenon has not been studied in ADHD children, two competing hypotheses may be advanced about the potential effects of manipulations of reinforcers and task/instructional parameters on the intrinsic motivation of ADHD children. First, ADHD children may be more vulnerable than normal children to the potential undermining of intrinsic motivation due to their tendencies to display an external locus of control, fail to persist in the face of failure, and may be more susceptible to the potential distracting effects reward. Alternatively, since ADHD children tend to show low initial interest in academic activities and since the beneficial effects of behavior therapy on academic work may enhance self-esteem, they may be less susceptible to reinforcement-induced loss of intrinsic motivation. It will be the purpose of the proposed research to address these issues by manipulating various reinforcement and task/instructional parameters and examining their effects on cognitive performance and intrinsic motivation of both ADHD and normal children. In addition, beginning in project year 4, the PI will begin work on an RO1 to propose the evaluation of specific treatment procedures based on the results of the initial studies.